1. Field of the Invention
This invention relates to a combustion apparatus and, more particularly, to combustion apparatus having the features of both fireplaces and furnaces.
2. Description of the Prior Art
The heating of homes is primarily accomplished by furnaces using either gas or fuel oil as a fuel. Past generations have also used wood and coal as fuels. A typical furnace installation includes the use of a blower which passes air over or around a combustion chamber or chambers and by a heat exchange process the air is warmed. The warm air is then circulated throughout the home or structure in which it is located by a network or system of ducts. The combustion gases are vented to the atmosphere through a chimney flue arrangement.
Another method of heating a home, such less efficient than a furnace, is a fireplace. The fireplace is, of course, a much older method of heating a home, and is not used primarily in contemporary structures for heating a home, but rather is used for aesthetic purposes, with heat derivation a secondary purpose. Typically, a fireplace puts out only a limited amount of heat into the room in which it is disposed. An improvement over the "normal" fireplace is the so-called "heatalator" fireplace in which a metal shell is inserted within a brick (ceramic or rock) facing. The metal shell comprises the combustion chamber and thence through the facing allows air to circulate to a limited extent about the metal shell for heat transfer purposes. The heated air is then vented to the room in which the apparatus is disposed. There are other variations of the "heatalator" apparatus, but they function basically in the same way.
Another type of fireplace apparatus, somewhat more efficient than the enclosed fireplace, is the free-standing fireplace which is a metal shell disposed in a room. This type of apparatus is more efficient than that described in the previous paragraph due simply to the fact that air from a room circulates around the combustion chamber shell and thus more heat is exchanged. An additional advantage in the free-standing fireplace is that a wall is not needed, and the expense of a hearth and the masonry associated with the built-in type fireplace is eliminated.
Wood is the principal source of fuel for virtually all types of fireplaces. Regardless of the type of fireplace, wood is virtually the only type of fuel burned. Andirons or some other type of grate is disposed in the fireplace and the wood fuel is disposed thereon for combustion purposes.
In the heating apparatus described above, the type of fuel is extremely limited. The limitations are imposed by the apparatus themselves, with respect to the furnaces, and, with respect to the fireplace, the limitations are due to the inherent characteristics of fireplaces particularly with their limited ability to provide sufficient air (oxygen) for the combustion of various types of trash or refuse whose burning characteristics are different from ordinary wood, such as logs. The types of trash available for combustion, and which produce substantial heat when burned, include newspapers, cardboard, sawdust, wood chips, rubber dust, dried organic material, and the like.
Incinerators are virtually the only type of combustion apparatus which may burn such refuse. The availability of refuse, and the decreasing availability of wood logs, and the like, for formal fireplace consumption, and the decreasing availability and higher costs of gas, heating oil, and the like, make the use of trash an attractive fuel, provided the problems associated with trash may be eliminated.
Among the problems associated with the burning or combustion of trash are smoke, odor, increased oxygen demands, and ash residue. Heretofore, only expensive incinerators, such as commercially used, were able to overcome the problems to even a limited extent with respect to the combustion of trash.
The apparatus of the present invention combines the features of furnaces, fireplaces, and incinerators, in providing a relatively efficient heating apparatus for homes and the like, and allows the use of a very wide range of materials for combustion purposes. Trash, as well as wood, may be burned in the apparatus of the present invention without the problems of odor, pollution, and the like.